The present invention relates in general to manufacturing building blocks and pertains, more particularly, to a molding machine for manufacturing building blocks for use in a retaining wall system. The molding machine of this invention is an improvement over the conventional molding machines now in use to manufacture the proprietary building block.
With the conventional molding machines it is generally necessary to provide a complex, relatively slow combined translation and rotation of a mold for a building block as set forth in U.S. Pat. Nos. 4,379,659 and 4,521,138, both for building blocks. A machine for molding these building blocks is known and its design and operation, along with the building blocks and their uses, as disclosed in the identified U.S. Pat. is presumed known and incorporated herein by reference.
Their may be one or more U.S. Pat. or foreign patents issued that disclose the conventional molding machine. Their identity has not been determined as of the filing of the present application. Those familiar with the building blocks are well aware that turning a mold over and removing the molded building blocks from their mold requires a combined rotation and translation movement. This complex articulation of the mold is required in part due to the fragility of the molded building block after it is released from the mold and before it is cured.
In spite of almost a decade in which to improve the conventional molding machine, the mold is still moved through the complex motion. Another drawback associated with the conventional molding machine is its relative slowness due at least in part to the following factors. One factor is the weight of the mold and its inherent inertia that precludes rapid movement.
Another factor is the fragility of the molded building block before curing. A quick movement of the mold back, up, forward, and down, would likely, it is feared, ruin the uncured building block, possibly by distorting it in the mold.
It will be understood that the building blocks manufactured by the molding machine of the present invention include those identified in the referenced United States patents and other known blocks and those blocks that may be later developed for use in association with the LOEFFELSTEIN brand retaining wall system. It will be further understood that the molding machine of this invention is suitable for use in the molding of any block that cannot be stripped through a conventional block form.
Existing concrete block forms also have a drawback related to the manufacture of any block that has a base or must be molded upside down. As an example, conventional splash blocks are made by hand to this day because of a lack of a molding machine that allows a mold to be turned over in order to strip the mold.
Accordingly, it is an object of the present invention to provide an improved molding machine that is adapted to increase the number of building blocks molded in a given period of time. The rotational motion of a mold provided for in the present invention is intended to save both time and the expense of improperly molded building blocks.
Another object of the present invention is to provide an improved molding machine for the LOEFFELSTEIN brand WATERLOFFEL brand pre-cast concrete module. It will be recognized that the molding machine of the present invention may be adapted to provide a pre-cast concrete block or module configuration to any number of shapes, dimension tolerances, unit density or weight, and concrete strengths in which utilization of the rotating mold and translating receiving assembly results in an improved molding process.
A further object of the present invention is to provide an improved molding machine that is adapted for incorporation into an otherwise conventional molding machine with its collecting hopper and feed box combination, pallet receiver, release conveyor, and appropriate mold.
Still another object of the present invention is to provide an improved molding machine that may be readily operated by a small, appropriately trained crew to further increase the molding machine output and reduce the cost of the building blocks.
Still a further object of the present invention is to provide an improved molding machine that is adapted for integration with the conventional items required for the operation of the conventional molding machine and not illustrated in the drawings, including the following; a cement storage system; sand and aggregate bins; concrete mixer; conveyors for cement, sand, aggregate and mixed concrete, including conveyor to a feed box; air compressor system; electrical service; mold release agent and associated spray unit; curing room conveyors; overhead crane, if required; drying lids, plywood for clamping mold, pallets and necessary pallet handling equipment.
Another object of the present invention is to provide an improved molding machine that incorporates the desired molding block handling features of the present invention while allowing the mold to receive the proper degree of conventional pneumatic compaction pressure and vibration.
A further object of the present invention is to provide an improved molding machine that is adapted to accommodate a mold that must be turned over in order to strip the molded block from the mold. A block that has a base or solid portion, e.g., splash block, is molded upside down, thereby requiring the mold to be turned over to strip the block from the mold.
The present invention provides a replacement for the conventional hand molding process still being practiced to manufacture pre-cast concrete blocks that cannot be stripped through a conventional mold.
Still another object of the present invention is to provide an improved molding machine that reduces the molding cycle time over conventional molding machines. The molding machine of this invention has displayed the ability to reduce the molding cycle by possibly as much as one third over the molding cycle of the conventional machine. It is believed that the present invention may reduce the molding cycle from 90 to 60 seconds, depending upon the skill of an operator.